Why You Should Never Fertilize Your Lawn During A Drought

Lawns typically need fertilizing to provide nutrients lost to other plants in the landscape and activities such as mowing, which not only stresses the lawn but often removes the nutrients that come from grass clippings. Experts on turfgrass recommend fertilizing one to four times annually, depending on several factors, such as the kind of turfgrass you have and how much maintenance you're willing to put in. But there's one condition under which you should not fertilize: during a period of drought.

Under drought conditions, photosynthesis is limited by the lack of moisture, and plant growth slows. Your lawn may deplete its stored energy supply trying to survive. Fertilizer is largely aimed at leafy growth, so if you're fertilizing your lawn during a drought, you're encouraging it to grow taller or produce more shoots instead of deeper roots, which are needed for hydration. But it's hard for a plant to add top growth when it's thirsting for water. You might grow plenty of blades of grass if you fertilize in a drought, only to have them suffer in arid stress. That's why drought application is among the things you should never do when fertilizing your lawn. 

During times of drought, you should avoid using a lawn fertilizer that contains nitrogen. Because of its association with plant growth, nitrogen is the key fertilizer ingredient that's problematic during a drought. Nitrogen's focus is foliage growth (in this case, blades of grass) rather than the deep root system grass needs for survival. With roots weakened, the grass blades are also weaker and subject to damage. 

Drought can also exacerbate the toxic effects on roots of high salt content in some fertilizers, causing leaf (blade) necrosis that starts with browning. Fertilizer burn is another possible result of fertilizing your lawn in a drought and is characterized by problems with water uptake, yellow or brown leaf blades, and a scorched appearance. Finally, consider the amount of water needed to dissolve water-soluble fertilizer during a drought, a time when conservation is important.

At some point under severe drought conditions, your lawn may enter dormancy to shield itself from the effects. Grass will completely cease growing and turn brown, appearing almost dead. You might be tempted to apply fertilizer to try to revive it. While you likely won't hurt the dormant grass by fertilizing, you also won't help it because under dormancy, the grass can't easily absorb the water carrying the fertilizer, meaning the product and the water will go to waste. It's best to just wait it out to fertilize until temperatures cool and water isn't in short supply. While you wait, focus on other ways to treat your lawn in the middle of a drought.